


Artificial Moon

by Velvet_Cosplays



Category: Sonic the Hedgehog - All Media Types
Genre: Ethical Science, Gen, It's just Eclipse in Shadow's place and vice versa, Laboratories, Medical Malpractice, Other Additional Tags to Be Added, Roleswap AU, Science Experiments, Space Colony ARK, Unethical Science, sibling relationships
Language: English
Status: In-Progress
Published: 2021-03-07
Updated: 2021-03-12
Packaged: 2021-03-13 23:09:53
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 4
Words: 4,577
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29908506
Author URL: https://archiveofourown.org/users/Velvet_Cosplays/pseuds/Velvet_Cosplays
Summary: What would happen if Eclipse and Shadow switched roles?~~~Planned arcs: The A.R.K - 06Current arc: The A.R.K
Relationships: Eclipse the Darkling & Maria Robotnik (siblings)
Comments: 7
Kudos: 6





	1. Chapter 1

Multicolored, watertight wires attached to electric pads that stuck to a deep grey-blue, almost black scaled hide. Three-fingered claws that twitched slightly when the surrounding scientists spoke too loudly. A long, whip-like tail that ended in a red stinger-like point.

Good. The subject seemed recognizable now, but his transparent skin showing his yellow ribs was... concerning. It looked underdeveloped, but it seemed to be completely formed. While he could be removed from suspension now, the modifications made to an otherwise alien brain weren't completely done, as the final change to his anatomy was giving him the ability to pack-bond with other species, which is extremely important if your base material is a naturally human-eating species.

Splicing his DNA with a Mobian hedgehog embryo helped greatly with toning his instincts to rip and tear down, and was the catalyst for the project to make an otherwise Black Arms soldier suitable for living in an enclosed space with easy prey.

The soft click of shoes on the tile floor approached the darkened room, only illuminated by the fluid-filled tube and the monitors. "...hey there." A soft, sweet voice greeted. One of the creature's claws twitched, and the young girl who had managed to sneak in smiled. "You can hear me, can't you? I can't wait to meet you." She sat down in front of the tube. "You're gonna be a good friend, I bet!" She laughed, watching as his tail flicked at the tip. "You like my voice, don't you, uh... I... haven't come up with a name for you." Her laughter died down as she started thinking. "My grandfather said something about a project called 'Eclipse'... something. Is that you? Are you Eclipse?" She questioned, though didn't expect a response.

"...I'm going to call you Eclipse, because the A.R.K. kinda looks like the moon, and it means 'child of the moon', I think! I read it in a book somewhere at least." She smiled, rocking back and forth as she watched him occasionally twitch.

A voice called through the hallway, making her turn her head. "Oh- grandfather's calling-! I'll be back, okay?" She called, promptly getting up and running away.

The creature seemed to have already bonded to that particular child, even though he wasn't conscious yet.

* * *

Cold.

That was the first thing he felt when the liquid drained and the pod opened, he just felt cold and uncomfortable and miserable. Air stung his lungs as he suddenly gasped, coughing as the want to just go back to being in the liquid flooded his mind.

He opened his eyes, immediately feeling the pain of a bright light in his sensitive, strange pupils, struggling to hide his head by curling up instinctually, shivering. Everything felt so wrong! Why was it so cold and bright?!

Something soft and somewhat fuzzy carefully wrapped around him, and he felt himself be lifted up by it, cautiously opening his eyes to see what had him.

There was a tall being clad in a white coat of some sort, with a blue covering over its face, shiny things over its eyes, and grey... fur? Fur, peeking out from the covering.

The light had been dimmed after seeing his distress, and the chill was starting to disappear as the liquid was dried off. Maybe this wasn't as uncomfortable as he thought it'd be, but he didn't have the energy to fight or really do anything, having used his only strength fighting against the light, so he decided to lean into the hold, letting his eyes close again.

The being holding him seemed worried, then pleased, carefully covering him with the fabric and carrying the creature to a penned-off box with a soft dog bed, gently setting him down in it and watching as the creature coiled up, tail overtop his muzzle.

It seemed that, so far, the experiment was going well. The subject survived and didn't attack anyone, and looked to be acclimating well.

Blue eyes curiously peaked in, blonde hair falling into her face that wasn't held back from the headband. "Grandfather," She began, stepping into the doorway. "do you have a name in mind for him? Or can I name him?" She grinned innocently.

"...I don't, but I was intending to call him something along the lines of 'Danger--'"

"What about Eclipse?" Maria suggested.

Gerald looked at her with an unreadable expression, though realized that naming the living project "Eclipse" would help with hiding the plans of the superweapon, and smiled warmly. "What made you think of that?"

"Well, it means 'child of the moon', and the Space Colony A.R.K. looks like a moon, and he was created here." She reasoned.

"...hm. I like it. Eclipse it is." Gerald laughed, his joy turning genuine quickly. "But right now Eclipse needs to rest, he got rowdy while we were releasing him, and that's pretty tiring to a little juvenile."

"Can I pet him?"

The question caught the scientist off guard. "I-- what?"

"Can I pet him?" Maria repeated, more slowly.

"...you might hurt yourself on his exoskeleton." Gerald tried to talk the girl out of it, but he seriously doubted the determination a little girl possessed. She sprinted over, immediately reaching out to touch the slimy, man-eating artificial experiment.

"...huh, he's kinda soft. Sorta squishy." She hummed, interested as she rubbed one of the fleshy fins between her fingers. "Is he always going to be this small?"

"No, he should grow to roughly a meter tall, he's currently only half of what he will be." Gerald put it in perspective as she continued to stroke the alien. "...he's a little baby and I love him." Maria said with earnest.

Gerald wasn't sure he had the heart to tell her what might become of the alien when the tests began.

"He'll get his own room later, right?"

"He doesn't need his own room, don't you think he'd prefer a crate? Eclipse likes to curl up already."

Maria turned to Gerald with a glare, one with more power behind it than it needed.

Gerald stared back, surprised by how intimidated he felt by the child. Well, to be fair, she currently had the head of a sleeping monster in her hand and a certain Robotnik craze to her, it ran in the family after all.

"...I'll request an order for a room when he outgrows the crate, alright?" Gerald tried to bargain, to which Maria stared at him for a few moments before eventually agreeing. "Fine, but you have to make it comfy."

"I promise I will. I'll try to simulate his natural environment." Gerald stated, putting a hand over his chest in promise. "Also, once you're done petting him, I advise you wash your hands."


	2. Chapter 2

It had been a few weeks since the project was woken up.

Not a single scientist on the A.R.K could have anticipated him forming such a bond to Maria, one that seemed so similar to how the Black Arms reacted to each other from the reports on their behavior. After all, studying the aliens was important to figure out how to approach Project Eclipse, as much as Maria hated the title "Project", insisting his name was just "Eclipse", it wouldn't be disappearing from the files any time soon.

A handful of scientists began to bustle into a meeting room, with Gerald at the head chair.

"Dr. Gregolian has put in a complaint recently, one regarding being assigned to the project." Gerald hummed. "He's claiming that the project has made attempts to attack him, but there's no footage supporting or denying that claim."

"He's not been wearing the proper equipment for the lab. Isn't there a sign about wearing protective gear when interacting with Project Eclipse?" One of the doctors asked, straightening her papers on the table. 

"He continues to wear sandals and standard, medical-grade lab safety equipment instead of the military-grade kevlar we've been provided." Gerald nodded to her. "If Dr. Gregolian continues this behavior, then he will be removed from the project the moment he makes a single mistake, as it won't be human error or machine failure, but just ignorance, and Project Eclipse is too precious to risk on an unprofessional." 

"I agree." Professor Valdez added. "I also wanted to request clearance on using reasonable force?" He asked.

Gerald looked to him, waiting. 

The professor took a breath. "The project has begun showing aggressive behavior to Maria Robotnik's care staff. I have reasonable evidence to believe he thinks they're hurting her, as he seems to have a pack bond to her. I've observed over the cameras that Project Eclipse responds to Maria in the same way we've been told Black Arm larvae respond to each other, which is trying to group together and move in a unit for safety, but this isn't a behavior displayed in anything other than juveniles." 

"And you want to punish him for showing trust to my granddaughter? The sole reason that I greenlit this project?" Gerald sounded aggravated. "You're forgetting the project's brain is formed more like a Mobian's. While he may have the instincts and behaviors of a Black Arm, he's intelligent enough to relate Maria with pain. Until he makes any attempt to attack, he will not receive any negative reinforcement. Tell me, Professor Valdez, how would you feel about being the reason a naturally human-eating species on board the A.R.K, also known as an enclosed environment, sees you and your species as a painful enemy?" 

Professor Valdez paused, caught off guard. "I-... see your point, Professor Robotnik. Then how do we discourage those behaviors?"

"Positive rewarding. Show that what's happening to who he sees as a packmate isn't scary or hurting her, and is instead helping. While there hasn't been any foods cleared for consumption by the project, I'm sure we can find another way to reward him for staying out of the way." Gerald reasoned. "Not everything done with these violent creatures has to be violent for them to understand." 

A heavy, meaty thwap was heard from outside the door. Gerald stood up from his chair, already knowing what was happening, and hurried to open the door a crack to see whether everything was alright. 

He looked in on Eclipse next to the door, struggling with his slime coat to get up on the smooth tile. Maria was there as well, rushing to his aid and picking the small alien up. "You okay?" She asked, shifting him in her grasp to carry him like a large cat, looking him over for wounds, only finding a bruise from the impact of slamming into the wall. "That's better than it could have been... c'mon, let's get you back to your box." Maria then promptly walked away, still holding the young creature.

Gerald watched for a few moments, then opened the door more. There were some quickly-evaporating trails of slime on the floor, which ended in small puddles that had two-toed pawprints walking back toward a source, just to have another trail next to it. One trail was much longer than the others, leading directly to the wall with a small amount of slime in a splatter on it. Well, he could figure out what happened from what was before him.

The professor closed the door again, going back to his chair. "...Maria has also bonded to the project. Punishing him would be much like witnessing a beloved pet be abused to her. I am only permitting the most minimal use of fully non-lethal force in situations where Project Eclipse is actively causing significant injury. I want you to use your best judgment of what 'significant' is, but accidental cuts on his exoskeleton and claws do not count. Neither does curious teething, but if it's visibly done with malicious intent, you may push him off with minimal force." Gerald set the ground rules down firmly, a look to his eyes that, even behind his glasses, looked like he wasn't willing to argue what was said. 

"Are you all in agreement?" Gerald asked, scanning the room and expecting nothing less than absolute agreement, which he received. "Good. The meeting is dismissed, as I feel all concerns have been addressed." Gerald hummed, standing up. "Be aware of the slip hazard outside." He warned, then left the room, walking toward one of the laboratories where Eclipse resided.

He looked in, watching Maria carefully apply a painkiller to the bruised fin. "There you go... that feels better, doesn't it? Or it will soon, at least. Sorry if it's cold right now." She smiled softly, stroking the alien from his forehead to the tip of his center fin.

"Am I interrupting anything?" Gerald chuckled. Maria quickly looked up like a deer in headlights combined with a guilty dog, as if trying to fix her mistake was a crime. "Don't worry, you aren't in trouble. Let me see what you're using." Gerald went to sit next to her, taking the ointment from her and looking at it, then gave it back. "Good choice, this one is clear for sensitive skin." He praised.

Maria beamed, her startled state quickly becoming a forgotten memory. "I saw this is the one that always gets used for accidents." She explained her process.

"Good observation." Gerald chuckled. "You're becoming quite the little scientist. I can't wait to see what you'll be. Project Ecli-"

"His name is just Eclipse."

"...Eclipse is a good starting point for care. He doesn't hurt you, right?" Gerald asked, just to be safe.

Maria looked down. "Well... about that. Sometimes I get scratched if I hold him wrong, but he's never done anything to hurt me. This... isn't the first time I gave him a bruise, he's really soft and I get excited--" 

"It's alright, you're careful and those are accidents, plus you help to take care of the aftermath instead of pushing the responsibility onto someone else." Gerald reassured. "I bet he forgives you."

"Yeah. I bet he does." Maria giggled, a smile on her face.


	3. Chapter 3

**Notes for the Chapter:**

> Author's Warning: An I.V is used, there's a discussion of someone's toe being eaten, and a medical examination.

It had been a few months since the project was released. He was adapting quicker than expected, being roughly fully grown and intelligent.

"Hey, wait up!" Maria called.

The hybrid looked back, then slowed his run to be beside her. "Sorry." He gave an apologetic smile, yellow fangs in full view. 

"You've been getting too excited since they gave you those shoes." She chuckled, promptly rubbing his head, briefly forgetting he was slimy and awkwardly pulling her hand away, proceeding to rub it on her dress. It'll evaporate eventually.

"Rubber shoes. Plus, they're just for moving on tile, they know I can't walk too well without them." Eclipse shrugged, shoulder spikes gently clinking against his soft exoskeletal armor.

"Y'know, when you g-"

"If."

  
"If you get grounded, all they need to do is take your shoes and then if you try to leave your room, you slide around until someone saves you." Maria laughed. 

"C'mon, I'm better behaved than you!" Eclipse challenged playfully. 

"I didn't eat someone's toe when I was a baby."

"Dr. Gregolian deserved it. Plus, 'he didn't follow proper lab safety procedures, and thus it is a result of human ignorance'." The alien quoted the scientist he overheard.

"Anyway, look where we are." Maria pointed straight ahead, at a sign reading "SUPPLY SHIP DOCKING STATION".

The two slowed down as they reached the area, with Maria suggesting to hide and Eclipse following her lead.

Gerald stood at the station, watching as a handful of people began unloading the unmanned ship, overseeing that everything was handled as it should be. "Place the food on the left side of the palette." He directed. "It will be brought to the cafeteria when possible. Personal belongings go on the right." 

"What about these, Professor Robotnik?" One of the lifters asked, holding up a box with perishable labels, and labels warning that the contents weren't for human consumption. 

"Leave that in personal belongings for now. I will retrieve them myself once you're done." 

Maria watched closely, then looked to Eclipse. "Smell anything?" She whispered.

The alien raised his muzzle to the air, flicking his neon green tongue out. "...kinda... I don't know- metallic? It's coming from that box that the professor wants. Also, I think there's fabric in the personal belonging pile." Another flick. "Yeah, I can smell softener!" Eclipse grinned. 

Maria beamed. "Oh heck yeah, new clothes! Think I'll get a lab coat too?"

Eclipse made an "I don't know" sound, then turned to watch again.

The ship had been entirely unloaded, the airlock was sealed, and it was sent back to Mobius. Now the crew was starting to work on taking everything to its appropriate place.

"...c'mon, let's get out of here before we're caught." Maria grinned, then took Eclipse's claw and started running with him, scurrying back to her room. While Eclipse was still learning the layout, she knew it well. 

Maria jumped onto her bed, sitting down and crossing her legs. "C'mon up." She beckoned, arms open and ready to catch the alien. 

Eclipse nodded, trying to figure out what to do for a moment before crouching, hands firmly on the ground before leaping like a cat, throwing himself into Maria's grasp and getting caught with relative ease. Even if he missed his jump, he trusted Maria would still help him, no matter what.

Maria was always there for him.

* * *

While being tied down and muzzled wasn't the most comfortable thing, the cushioned chair he was held to was... relatively comfortable. Eclipse understood it was because those scientists that he didn't bother to learn the names of were scared of him, which didn't make sense. If they thought he was going to eat them, they wouldn't leave him unsupervised around Maria.

Maybe they thought he only wanted to eat the scientists and not Maria? But it still didn't make sense, he didn't eat anything, surviving on the nutrient-filled I.V they would attach to him during these tests. Usually they weren't that bad, the worst one being falling asleep to something and waking up with a bandage along one of his ribs and an ache for a while. Eclipse couldn't speak back then, but he did remember that vividly.

He felt the muzzle being taken off, staying still so he wouldn't spook the scientists more than they probably already were, then one stood next to him and took two hooks on small metal rods, pressing it to his mouth until he opened it, then promptly getting the top and bottom of his jagged rows of teeth hooked and held open for inspection. 

Eclipse kept his bright tongue flat, allowing them to look over the yellow fangs. It looked like he had canines the whole way through, with only slight variations around where his molars would be, and much longer teeth where his canines usually would be. Soon, his jaws were let go of, and the muzzle was put on once again. 

He watched the scientists briefly bustle around, writing their findings down and discussing something out of earshot, then eventually they got to work on releasing him from his restraints and removing the I.V, but they always took the muzzle off last. Well, it was to be expected, that's where the terrifying teeth that they always jumped back or tensed up at when he yawned or smiled or even talked were. 

He was lead back to his room, being careful to show signs of submission, like keeping his head low and tail nearly on the ground, intentionally putting himself at a disadvantage for combat. 

Soon, Eclipse found himself in the small-ish room with its various mesh hammocks, vines, and carpeted black walls. It was meant to simulate a home that he never saw, so he could only assume this was accurate to where he was supposed to have come from. 

Eclipse watched the scientist leave and lock his door for the night, as useless as the lock was to stop him if he really wanted to break out, he assumed it was for peace of mind. The alien climbed up into one of the hammocks, tail and one leg hanging off it, and promptly went to sleep.


	4. Chapter 4

**Notes for the Chapter:**

> Author's Warning: Brief mention of eating a toe.

Leathery claws hit the ground in a three-point landing, knees bent to absorb the impact as their owner grinned, charging toward his opponent and trying to pounce on her.

Maria quickly and easily ducked, sending Eclipse flying over her shoulder with a yelp. The alien crashed into a table, scrambling back to his feet as he prepared for another attack, this time trying to trip her up with his tail when she tried to grapple him.

Maria squeaked as her knees were taken out from under her, but angled her fall to grab Eclipse anyway, dragging him down with her, resulting in the experiment being dogpiled beneath his larger human sibling. "Fine, fine! You win!" He cackled, wriggling out from under her with a new cut on his shoulder. It oozed a drop or two of neon green blood, though quickly began to heal over.

Maria smiled, trying to ignore the injury, knowing it was healing and getting worried over it would just ruin the mood. "You're getting better at playfighting." She commented. 

"Thank you, having an extra limb helps." He chuckled, getting up and helping his sister get to her feet. "Gerald's going to want to see us soon, right?" 

"I think so! He asked for you specifically, but I'm allowed to come if you want me t-"

"Stay." Eclipse cut her off, a soft desperation to his voice. "I- erh... I mean-- come with me please?" He asked, trying to hide the separation anxiety that was beginning to plague him.

Maria seemed caught off guard by the sudden desperation, but then gave a warm smile and carefully hugged him. "I'll always stay with you."

Eclipse relaxed into her hold, closing his eyes. "...thank you." He whispered. 

The two stayed in a hug for two minutes before Eclipse eventually felt ready to pull away. "...guess we should go?" He questioned.

"Yeah. C'mon, I'll bring you there." Maria gently took his claw, careful of the razor-sharp, flesh-rending points at the tip of each one, and began to lead the little alien away, back toward the laboratory. The other scientists realized that Eclipse acted differently when Maria wasn't around, being more hostile or apathetic, and it threw a wrench in the test results that weren't physical, so they had begun having her either in the room or just outside for most of the behavioral tests. 

Soon, the two arrived at the location. There was a chair against the wall where Maria usually sat, meant to be in Eclipse's view from where he sat at the sterile metal table in the center of the room.

He scurried onto the chair as Maria went to take her seat, turning his head to watch her, waiting patiently for the professor to arrive.

The click of footsteps caught his attention, quickly turning his head back to watch the door, observing as Gerald walked in, holding a plastic box of something. He couldn't smell anything, so it must be airtight.

"I'm glad you arrived on time without prompting, Eclipse." He hummed, placing the box in front of him, cracking open the lid. Eclipse flicked his tongue out, testing the air and immediately being hit with the same metallic scent he smelled from the supply shipment. 

Gerald reached into the box, pulling out metal platter with a slab of raw meat on top, with a handful of powdered supplements infused into it. "These are only iron, magnesium and potassium." He explained. "Enjoy."

Eclipse seemed confused at first, poking the recently-warmed meat with a claw tip, then moved his head closer and snapped at it with his teeth, obeying his instincts screaming at him to do so.

The alien was surprised by how easily his teeth slid through the meat, shearing cleanly through and leaving a delectable chunk on his forked, neon tongue. He held it for a few moments, then began to gnaw at it with his molar-like conical teeth, tearing it to tiny pieces that were swallowed easily. 

He quickly went back for seconds, picking up the entire chop of meat in his teeth and beginning to rip and tear at it, a violent and primal side of him coming out as his instincts were allowed their time in the spotlight.

Gerald stayed still, observing the experiment closely as he finished the chunk of meat, heavily breathing and still staring down, not blinking as his feeding frenzy began to settle again, eventually looking back up at Gerald. "...what was that?" He questioned.

"Pork. Generally, raw meat is not safe to consume, but this has been heavily screened and pasteurized before being given to you, so you'll be safe. How did it feel?"

"It felt... natural and energizing. Like that was what I was made to do."

"In a way, it is. Your species are obligate carnivores, which means you naturally only eat meat. We will be weaning you off I.V nutrients and replacing it with supplemented pork like this."

Eclipse beamed, tail gently thudding against the chair leg. "When? How much?"

"Hopefully once every other day, though your species is also accustomed to surviving starvation, so if the supply shipment isn't on time, then you will survive." Gerald reassured. 

Eclipse gave a nod. "So, what am I meant to hunt if I'm a carnivore?"

Suddenly, Gerald looked a lot more uncomfortable. "That is... irrelevant information." He halfheartedly explained.

Eclipse looked like he wanted to pry further, but nodded, understanding.

"You should return to your environment now." Gerald suggested, though his tone indicated an order. 

"Of course." Eclipse agreed, climbing off the chair, watching as Maria stood up and went to help lead him back. 

"So, how did the raw meat taste?" She asked, taking his claw again. "I've been curious about it, but I've never tried it."

"Squishy. Kinda slimy, not like me, but definitely wet." Eclipse tried to explain, accidentally making the delicious morsel sound disgusting.

"...okay?" Maria sounded confused, how could he even stomach it?

"I also only just learned what my teeth are for. I guess that's why they were getting inspected?" He offered, looking up to see his sister nod. "Grandfather told me of that." She hummed. "That's why someone lost a toe to you as a little baby."

"I'm still technically a 'baby'." Eclipse reminded with a grin. 

"You might be an infant by human standards, but you look and act 15." She put a hand on his head, rubbing his leathery scales and getting her hand coated in slime, rubbing it onto her own arms instead of onto her dress.

The scientists had determined it was just water and a harmless mucus, so why not use it like a moisturizer? It worked surprisingly well, she had to admit. 

Maria dropped him off at his room, exchanging goodbyes before locking him in, going back to her own room.

Eclipse watched the door for a few moments, then went over to the carpeted walls and rubbed part of his head and side against it, removing the dust that stuck onto him while playing with Maria, then climbed one of the vines up to the highest hammocks, curling up with his tail overtop his muzzle once he reached it, basking in the weak, purplish heat lamp at the top of his enclosure, drifting off to sleep.


End file.
